Method and apparatus for conversion of fluid hydrocarbons



Jun 29, 1948. G. L. JOHNSON I 58 METHOD AND APPARATUS FOR CONVERSION OFFLUID HYDROCARBONS Filed Aug. 14, 1946 4 Sheets-Sheet 1 BUCKET 515mm)REGEA/E/PHTOQ flv INVENTOR GEO/76E LJOfl/VS ON AGE OR ATTORNEY June 29,1948. G. L. JOHNSON METHOD AND APPARATUS FOR CONVERSIOE OF FLUIDHYDROCARBONS Filed Aug. l4, 1946 L N 6 0 w N 4 RH To 2W 5 1 l E 9 2 3 ma w} m 0 E G r 6 Z w f I /'/-I lW'f/H d 0 W, G, A ENT 0R ATTORNEY June 21948. G. L. JOHNSON METHOD AND APPARATUS FOR CONVERSION I OF FLUIDHYDROCARBONS Flled Aug 14, 1946 4 Sheets-Sheet 4 INVENTOR GEORGELJ'OHNSON AGENT 0R ATTORNEY Patented June 29, 1948 METHOD AND APPARATUSFOR CONVER- SIGN OF FLUID HYDROCARBON S George L. Johnson, New York, N.Y., asslgnor to Socony-Vacuum Oil Company, Incorporated, a corporationof New York Application August 14, 1946, Serial No. 690,371

9 Claims.

This invention has to do with a method and apparatus for conversion offluid hydrocarbons in the presence of a moving particle form solidcontact; material which may or may not be catalytic in nature. Exemplaryof the hydrocarbon conversion which may be conducted by this method andapparatus are the catalytic aromatization, hydrogenation,dehydrogenation, polymerization, isomerization, l alkylation, reforming,hydroforming, treating, desulfurization, and cracking of hydrocarbonfractions. Also exemplary are the viscosity breaking, cracking andcoking of heavy liquid hydrocarbons in the presence of a hot solid inertmaterial. This invention is particularly concerned with processeswherein the contact material moves cyclically through a conversion zonewherein it flows as a substantially compact column of moving solidparticles while being contacted at suitable elevated temperatures withfluid hydrocarbons either in the gaseous or liquid phase or both toeffect their conversion and then through a revivification zone \whereinit flows as a substantially compact column while being contacted with asuitable revivifying gas which in many instances maybe air acting toburn off from the contact material a carbonaceous contaminant depositedthereon during the hydrocarbon conversion. When the contact materialemployed is catalytic in nature it may take'the form of natural ortreated clays such as fullers earth and Super Filtrol, bauxites,activated alumina, activated charcoal, inert carriers bearing depositsof catalytic metallic oxides, or synthetic associations of silica,alumina or silica and alumina to which may be added smallpercentages ofother mate-'- rials such as certain suitable metallic oxides. When thecontact material employed is non-catalytic in nature, i; e., inert tothe reaction, it may -form contact mass material. During thisparticula-r reaction as is the case with many other hydrocarbonconversions, a carbonaceous contaminant is deposited upon the particleform solid. If the contact material is catalytic in nature, thecontaminant deposit substantially reduces its catalytic activity. If thecontact material is non-catalytic in nature, the contaminant deposit maygradually increase the particle size of the contact material to anundesirabledegree while at the same time small particles of cokymaterial having an undesirably small diameter tend to accumulate in themoving contact mass. In any event, it is usually desirable to effect theremoval of the contaminant deposit from the contact material. This maybest be accomplished in a revivification chamber separate from theconversion chamber. In the case of'inert contact materials, thecarbonaceous contaminant may in many cases tend to break off the contactmaterial particles and be-susce'pti ble to removal from the mass byentrainment in a suitable gas passed through the mass. On the other handsteam and/or air may be introduced into the hot contaminant bearingcontact mass to cause the carbonaceouscontaminant to undergo a producerborundum or zirkite; the material used preferably having a high thermalheat capacity and being highly resistant to breakage, cracking andabrasion. In any case the particle size of the solid material employedshould fall broadly within the range .007 to 0.75 inch and preferablywithi in the range of about 0.25 to 0.50 inch.

One of the most important processes for which this invention is adaptedis the cracking conversion of high boiling fluid hydrocarbons to lowerboiling gaseous hydrocarbon products containing gasoline and/or lowerboiling hydrocarbon products in the presence of a hot particle or watergas reaction. Other reactions are also available. In the case ofcatalysts, it has been found best to regenerate the catalyst by blow.-ing an oxygen containing gas therethrough to burn off the contaminant,while withdrawing excess combustion heat from the mass in order toprevent the catalyst temperature from rising to a heat damaging level.Commercially, in order to permit a practical overall unit structuralheight, it has been found desirable to position the conversion andrevivification vessels side by side at substantially the sameelevational level and to provide two contact material conveyors, one forconveying used contact material from the conversion vessel to therevivification vessel and one for conveying revivified contact materialfrom the revivification vessel back to the conversion vessel.

In such cyclic processes catalyst fines gradually accumulate in thecyclically moving stream of catalyst due to gradual attrition of theparticles falling within a predetermined normal size range. Such finesinterfere with the proper operation of the conversion and regenerationapparatus and seriously reduce the capacity thereof; For this reason theaverage percentage offines in the cyclically moving stream of catalystshould be maintained very low, for example, of the order of 1 to 5 percent by weight, Since the fines formed rom attrition become distributedin the moving treamof catalyst, and 'slnce" the total amount of catalystcirculation is-very high and thepercentage of lines therein very low',thecontinuous removal of fines from the'dyclically moving stream ofcatalyst is} costlyand 'difllcult process. j

A major object of this invention is the provision in a continuousconversion process" wherein a stream of contact material passescyclically.- through a hydrocarbon conversion zone and. a regenerationzone of an improved method and'ap paratus for removal of fines formed byattrition from the cyclically moving stream of contact. material.Another object of this invention isthe provision of an improved conveyorforconveying hot particle form contact materials in acyclic [fluid maybe introduced to the tubes through inlet 24 and withdrawn through outlet25. It will beunderstood that the inventionis not restricted to'anyparticular reactor andregenerator construction. These vessels may, ifdesired, be adapted for countercurrent flow of gas and solids conversionsystem. These and other objects will become apparent in the followingdiscusslon'of the invention,

The instant invention broadly involves the.

provision in a cyclic conversion process of meth-' I 0d and apparatuswherein particle form contact material is passed through a downwardlysloping feed chute into buckets in a continuous bucket elevator..Foraminate partitioning in the buckets defines a separate settlingcompartment in each bucket into which fines carried in the contactmaterial separately settle. The fines and normal-sized contact materialare separately discharged from the buckets at the upper end'of theelevator.

The invention may be best understood by-reference to the attacheddrawings in which Figure 1 is an elevational view showing a cyclicconversion process arranged according to the teaching of this invention;

and they may be of the multi-stage variety.

In operation used contact material passes through sloping conduit orchute I8 from reactor ill to elevator 13 by which it is conducted toconduit 22 feeding the regenerator. Regenerated contact material passesfrom regenerator at I through sloping conduit 32 to elevator l2 by whichit isconducted to duct 34 feeding the reactor supply hopper l6.Separated fines may be withdrawn from the upper sections of elevators l2and I3 through conduits 26 and 21 respectively delivering intoaccumulator 28.

Turning now to Figures 2, 3 and 4 which may be best considered togetherfor a more detailed study of the construction of the elevators. It willbe seen that the casing of each elevator is made up of a foot portion, ahead portion and an intermediate portion. The casing may be made up'in asingle section but it is preferably made up of a plurality of flangedsections and generally at least of three sections, namely, a headsection, an intermediate section and a foot section. Within the casingis provided an endless Figure 2 is an elevational view, partially insection, showing -an assembly view, of one. of the elevators shown inFigure 1;

Figure 3 isa sectional view taken along the line.

33 in Figure 2; 7

- Figure 4 is a vertical sectional view of the upper end of the conveyorshown in Figure 2;

vessel Ill, a regeneration vessel II and elevators l2 and 13 fortransferring solids from one vessel to the other. Hydrocarbon reactantsheated in a conventional external system (not shown) may be introducedinto the upper section of the conversion vessel through inlet [4.Gaseous conversion products may be withdrawn near the lower end ofvessel l0 through outlet l5. Particle form contact material may besupplied to the upperend of the vessel l0 from supply hopper l6 througha gravity. feed leg l1. Used contact material may be withdrawn from thelower end of vessel Ill through outlet conduit l8 bearing flow controlvalve IS. The outflowing contact material may be purged free of reactantgases by means of a purge gas such as steam or flue gas introduced intovessel I0 through conduit 20.

A seal of steam or flue gas, etc. may. be maintained adjacent the upperend of the reaction zone by introduction of a suitable seal gas throughconduit 2|. The regenerator ii is provided with a solid inlet 22 at itsupper end and a series of buckets which preferably overlap to a limitedextent substantially as shown in Figure 2. Referring to Figure 3, a headshaft 9| passes through the casing in the head portion and two spacedapart wheels 92 and 92 are provided on the head shaft. Continuous chains93 and 93' are trained over the wheels 92 and 92' so as to form a loopin the head portion of the casing and a second loop in the foot portion.The chains may be guided by guides indicated by the dotted lines 94attached along opposite sides of casing 12 and by means of the guidewheels 98 at the foot loop. In some constructions the wheels 98 may beomitted. The head shaft is driven by an externally located drive wheeldriven in turn through chain 9-6 by motor 91. The buckets 90 may takeany of a number of crosssectional shapes, a preferred shape beingapproximately that indicated in Figures 5 and 6. The buckets areattached on their opposite ends to the'two chains 93 and 93" in such amanner as to open outwardly of their closed path of travel and in such amanner as toopen outwardly and upwardly as they move upwardly adjacentthat side of the casing l2 into which the feed chute 41 connects and asto be inverted as they move down- Wardlyadjacent that side of the casingl2 into which the discharge chute 48 connects. The buckets are furtherso shaped and fastened to the chains 93 and 93' that in passing over thehead loop or the wheels 92 and 92', each bucket discharges contactmaterial onto one side of the inverted bucket movingimmediately beforesaid firstnamed bucket and the side of the last named V inverted bucketis so sloped as'to direct the consolid outlet 32 on its lower end.Regeneration tact material into the discharge chute 48. It

will be noted that the discharge chute extends into the conveyor casingto such an extent that I V agitate the chute opening is close to theedges of the.

buckets as they pass downwardly in their path.

The arrangement is such that the contact material is poured from thebuckets into the discharge contact material from the buckets into thedischarge chute with very little spillage 01 contact material occurring.The feed chute 41 similarly extends a short distance into the casing 22so as to terminate just opposite the edge of the open a tops of thebuckets 90 so that contact material pours directly from chute 41 intotheupwardly.

moving buckets 90 without substantial spillage of contact material intothe foot section of the casing. v

For a study of the bucket construction, Figures 5 and 6 should beconsidered'along with Figures 2, 3 and 4. Within each bucket arepositioned foraminate partitions I M and I02 which extend the horizontallength of the buckets. These partitions define within the bucket 90 aninner-compartment I03 for receiving and carrying the contact materialand an outer compartment I04 for receiving the fines, The .partitions I!and I02 are perforated with holes I 06 having a diameter approximatelyequal to that of the fines which are to be removed from the contactmaterial. An opening I through that side of the bucket wall which 'is onthe inside of the path of travel is provided across the horizontallength of the bucket below the level of partition I02, thereby providinga discharge from the outer compartment I04. As will be seen from Figure4, the opening I05 is on the up side of the bucket during the upwardtravel of the bucket in the casing I2. However, as the buckets passaround the head wheels 92 and 92', the opening I05 faces downward sothat the fines in compartment I04 are spilled into that portion ofeasing I2 within and Just below the head loop formed by the chains andbuckets. A receiving funnel I01 which extends across the casing 22 thefull horizontal length of the buckets 90 is positioned within the casinghead section to catch the discharge fines. The fines may then bewithdrawn through conduit 26. It will be clear from. Figure 4, thatwhile the fines are discharged'within the head loop, the normal sizedcontact material is separately discharged into discharge spout 48 on theoutside of the head loop. It will benoted that vanes I08 and I09 areprovided on both ends of each bucket on that side of each bucket ontowhich contact material is poured from the next bucket on the chain inthe conveyor head section. These vanes provide a passage for dischargednormal sized particles into the discharge chute 48 and prevent the solidmaterial from falling oil the ends of the buckets.

Turning to Figure 7, there is shown a detailed view of a section of oneelevator chain 93' and of the bucket attachment thereto. It will be seenthat the chain is a knuckle chain of the offset type. Each link has nearone end a knuckle H0 in which is a bushing indicated by dotted lines atI I I, A chain pin I I2 fits through the bushing II I and through holesin the ofiset side bars of the next link. A keeper pin II3 may beemployed to hold the chain pin in place. To each end of the bucket iswelded or bolted an attachment bar or bracket II4 which in turn isbolted to one of the elevator chains such as chain 93'.

This invention takes advantage of the tendency of undersized solidmaterial to segregate along the underside of a stream of solid particlesflowing downwardly in an inclined chute and the tendency oi undersizedparticles to concentrate near the bottom of an accumulation of contactmaterial maintained in a vessel which is subjected to agitation orvibration. rial stream containing some fines passes from vessel II inFigure 1 through a downwardly sloping chute 32 into the buckets 90 inelevator I2. By the time the contact material stream reaches the lowerend of chute 32 some of the fines have settled on the underside oi thestream and are directed into that portion of the buckets 90 nearest theioraminate partitions ml and I02. As the buckets pass upwardly throughcasing I2 they are subjected naturally to considerable vibration andagitation which results in the settling of more fines to the bottom ofthe solid accumulation in bucket compartment I03. Fines pass through theholes I08 in partitions I M and I02 into the fines receiving compartmentI04, and the fines are then separately discharged fromthe elevator ashas been described hereinabove. The method and apparatus of thisinvention may be applied'to both elevators in a cyclic system asdescribed or to either elevator alone. It will be apparent that sinceconveyors and the sloping solid feed chutes thereto are alreadya portionof conventional cyclic conversion systems, the method and apparatus ofthis invention permits the removal of fines from the cyclically movingcontact material stream in such systems by an easily made improvement inconveyor construction and without the requirement of any addedclassification apparatus.

It should be understood that while the particular form of elevator andconveyor construction shown diagrammatically in the drawings is apreferred form of the invention, nevertheless the rial which comprises:passing said contact material through a conversion zone wherein itcontacts fluid hydrocarbons under conversion conditions to effect theconversion of said hydrocarbons and through a reconditioning zonewherein it is contacted with a suitable gas to recondition it for reusein said conversion zone, removing used contact material from saidreconditioning zone, continuously flowing it through an elongateddownwardly sloping passage into the lower section of a confined,elongated conveying zone, conducting said used contact material upwardlythrough said confined elongated conveying zone, subjectingsaid contactmaterial to classification to separate undersized particles from normalsized particles during the upward passage of said contact material insaid conveying zone, separately discharging the separated undersizedcontact material from the upper section of said conveying zone andremoving it from the cyclic process, separately discharging theremainder of the contact material from the upper end of said' conveyingzone and passing it to said conversion Thus a contact matezone andreturning used contact material from said conversion zone to saidreconditioning zone.

2. In a process for conversion of fluid hydrocarbons in the presence ofa particle form solid contact material wherein the contact material ispassed cyclically through a conversion zone while contacting it thereinwith a fluid hydrocarbon charge to effect its conversion and through arevivification zone while contacting it therein with a suitable gas torestore the contact material to a state suitable for is reuse in saidconversion zone, the improved method for transierring contact materialfrom one zone to another while eliminating undersized fines from thecyclic system which method comprises: passing contact materialcontaining fines from one of said zones in said cyclic system through adownwardly sloping confined passage into the-lower section of anelongated, confined conveying zone, conveying said contact materialupwardly through said conveying zone, subjecting said contact materialto screening to separate the fines from the remainder of said contactmaterial during its upward passage in said conveying'zone, separatelywithdrawing fines from the upper section of said conveying zone,separately withdrawing the remainder of said contact material fromtheupper section of said conveying zone and passing it to the other ofsaid zones in said cyclic system.

3. A method for the catalytic cracking con-' version of fluid petroleumhydrocarbons which comprises: passing a particle form catalyst down-tfrom said regeneration zone through a downwardly sloping chute into theupwardly moving containers within a confined, upwardly extendingconveying zone, conveyin said catalyst upwardly through said conveyingzone in such a manner as to cause fines to settle and separate from thenormal sized catalyst particles in said containers, separatelydischarging fines and normal sized catalyst from the upper section ofsaid conveying zone, removing discharged fines and passing thedischarged normal sized catalyst particles-to said conversion zone.

' 4. In a hydrocarbon conversion system wherein .a particle form contactmaterial is passed cyclically through a conversion chamber and areconditioning chamber, an improved conveyor for transferring contactmaterial from one of said chambers to the other which comprises: anelongated upwardly extending conveyor casing, an endless series ofarticulated buckets adapted to travel in a closed path in said casingwith said path looping in the upper portion and in the lower portion ofsaid casing, means to move said'series of buckets in said closed path,perforated partitioning in each of said buckets adapted to define aninner compartment for receiving contact material and an outercompartment for receiving fines from said-inner compartment, said outercompartment being in communication with said inner compartment throughthe perforations in said partitioning and being so positioned relativeto said inner compartment as to be generally below said innercompartment during the passage of the buckets through the upward portionof their path of travel, an outlet from said outer compartment sopositioned as to permit gravity discharge of fines from said outercompartment in the upper section of said conveyor casing, means defininga downwardly sloping feed passage for the fiow of contact material intothe buckets as they pass upwardiy in their path within the lower sectionof said conveyor casing, means to direct the flow of contact materialfrom one of said chambers in said conversion system into said feedpassage, means adapted to separately catch solid material dischargedfrom said inner and outer compartments of .said buckets near the upperend of said conveyor casing, means to pass the separately caught contactmaterial from the inner compartment of said buckets to the other of saidchambers in said conversion system and means to withdraw the separatelycaught solid material from said outer compartment of said buckets to anexternal location.

5. In a hydrocarbon conversion system wherein a particle form contactmaterial is passed cyclically through a conversion chamber and areconditioning chamber, an improved conveyor for transferring contactmaterial from one of said chambers to the other which comprises: anelongated upwardly extendin conveyor casing, an endless series ofarticulated buckets adapted to travel in a closed path in said casingwith said path looping in the upper portion and in the lower portion ofsaid casing, means to move said series of buckets in said closed path,perforated partitioning in each of said buckets adapted to define anupper compartment for receiving contact material and a lower compartmentcommunicating through the perforations in said partitions for receivingfines from said upper compartment, said lower compartment being providedwith a discharge opening so positioned as to permit separate dischargeof fines therefrom as the buckets pass over the loop in the upperportion of said conveyor casing, means to separately withdraw finesdischarged from said opening in the upper portion of said casing, meansto separately catch contact material discharged from said uppercompartments in said buckets in the upper portion of said casing andpassage defining means to direct flow of said contact material to one ofsaid chambers in said conversion system, and means defining a downwardlysloping contact material feed passage adapted to direct contact materialfrom the other of said chambers in said conversion system into the uppercompartments of said buckets as said buckets move upwardly in the lowerportion of said conveyor casing. a

6. In a conversion system wherein a particle -form contact material ismoved cyclically through downwardly moving buckets are inverted andupwardly moving buckets open upwardly and toward the outside of theirpath of travel, partitioning within each bucket providing in each bucketan upper contact material receiving pocket and generally therebelow afines accunrulation chamber, said chamber communicating with saidreceiving pocket through a plurality of small openings in saidpartitioning, an opening for removal of fines from said chambersopositioned as to prevent flow of fines from said chamber as long assaid buckets move in their upward path of travel, but as to permit thegravity fiow of fines through said opening as said bucket passes overthe upper loop in its path of travel, a receiving basin positionedwithin the head loop in said casing for receiving fines poured from saidfines accumulation chamber as said buckets pass over said head loop,conduit means to withdraw fines from said basin, a discharge spoutconnected into the upper portion of said elevator casing in a positionto receive contact material poured from the receiving pockets of saidbuckets means to pass contact material fromsaid discharge spout to oneof said chambers in said conversion system, and a downwardly sloping,elongated feed spout connected into the lower section of said elevatorcasing in a position to feed contact material into said receivingpockets in said buckets and means to pass contact material from anotherof said chambers in said conversion system into said fed spout.

'7. In a system of the type described a contact material conveyor andclassifier which comprises in combination: a substantially vertical,elongated elevator casing having a head section and afoot section, adownwardly sloping contact material feed spout connecting into one sideof said casing near its lower end, a discharge spout connecting into theopposite side of said casing near its upper end, an endless series ofarticu- .lated buckets within said casing, perforated partitioningwithin each of said buckets defining a receiving compartment open on oneend to receive contact material and generally therebelow a finesaccumulation compartment, communicating with said receiving compartmentthrough the perforations in said partitiong means to support said seriesof buckets and to cause the buckets to travel in a closed path, saidpath forming a loop in said head section above said discharge spout anda loop in said foot section belowsaid feed spout, said buckets being sosupported by said support means as to even outwardly toward the side ofsaid casing into which said feed spout connects during their upwardmovement in said closed path and as to be -inverted during theirdownward movement adjacent the side of said casing into which saiddischarge spout connects and said buckets being further so supportedthat each bucket in the upper section of said casing discharges contactmaterial from v its recelving pocket onto a side of the inverted bucketmoving in the closed path immediately before said bucket and said sideof said latter bucket is so sloped as to direct flow of contact theinverted bucket,'means to withdraw contactmaterial from said dischargespout, means to supply contact materialto said feed spout, an outletfrom said fines accumulation compartment in 'each bucket adapted toretain the fines in said compartment during the upward movement ofsaidbuckets and to'permit igravity discharge of fines from saidcompartment in each bucket as the bucket passes over the head loop, anaccumulation basin positioned within the head loop in said casing forseparately receiving discharged fines, and means to withdraw fines fromsaid basin.

8. A contact material conveyor and classifier which comprises incombination: an elongated communicating with material into saiddischarge spout, vanes iascompartment, said lower compartment beingprovided with a discharge opening so positioned as to permit separatedischarge of fines therefrom in the upper portion of said casing. meansto move said series of bucket in said closed path,

means to deliver particle form contact material into said receivingcompartments in the lower section of said conveyor casing, means towithdraw fines discharged from said accumulation compartments in saidbuckets in the upper portion of said casing and means adapted toseparately catch and withdraw contact material discharged from thereceiving compartments in said buckets in the upper portion of saidcasing.

9. A contact material conveyor and classifier comprising in combination:an elongated upwardly extending conveyor casing, an endless series ofarticulated buckets in said casing, means to support said buckets and tomove them in a closed path forming a loop in both the head and the footportions of said elevator casing. in which path downwardly movingbuckets are inverted and upwardly moving buckets open upwardly,partitionin within each ofsaid buckets providing in each bucket an uppercontact material receiving pocket and generally therebelow a finesaccumulation chamber, said chamber said receiving 'pocket throughperforations in said partitioning, said accumulationchamber beingprovided with a discharge opening positioned to permit separatedischarge of fines'therefrom as the bucket passes over the loop in theupper portion of the conveyor casing, means in the upper portion of saidcasing to separately withdraw fines discharged from said opening, meansin the upper portion of said casing to separately withdraw contactmaterial discharged from said receiving pockets in said buckets.

GEORGE L. JOHNSON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 813,903 Lindhard Feb. 2'1, 19061,351,948 Fowler Sept. T, 1920 2,322,415 Buckbee June 22, 1943 2,350,730Degnen et a1 June 6, 1944 Simpson et al. Oct. 31, 1944

